The Data-Over-Cable Service Interface Specification (DOCSIS) was established by cable television network operators to facilitate transporting data traffic, primarily Internet traffic, over existing community antenna television (CATV) networks. In addition to transporting data traffic, as well as television content signals over a CATV network, multiple services operators (MSO) also use their CATV network infrastructure for carrying voice, video on demand (VoD) and video conferencing traffic signals, among other types.
Data traffic and signals are typically transported to subscribers in the form of internet protocol (IP) packets. Generally, when a transmission medium (e.g., cable, wireless router, EPON, etc.) is shared by a plurality of subscribers to access one or more of the various services (e.g., data traffic, television or voice signals, etc.) offered by a MSO, the resources associated with the transmission medium (e.g., maximum bitrate) are allocated between the one or more services being accessed by the plurality of subscribers at a specific time.
The need for low-latency packet flows varies with the type of application requesting a packet flow from a MSO. For example, online gaming generally requires a low-latency packet flow, while data transmissions via file transfer protocol (FTP) can be effectively completed through a normal or high-latency packet flow. Generally, when a transmission medium becomes congested with a plurality of data flows, the available resources of the transmission medium are allocated between the data flows, thus the bitrate available for each flow to utilize is typically reduced. When the bitrate available for a data flow is reduced to a rate lower than the rate at which data is requested, data packets are generally either dropped from the data flow or are buffered, thus increasing the latency of the data flow. A general prioritization of data requests from applications needing low-latency data flows can lead to an unfair disparity between the bitrate available to heavy users of low-latency data flows and the bitrate available to light users of low-latency data flows. Broad use of such a general prioritization over a transmission medium allows a subscriber's use of low-latency data flow to negatively impact the bitrate available to other subscribers accessing the same transmission medium. Thus, there is a need for improved quality of service for low-latency data flows.
Like reference numbers and designations in the various drawings indicate like elements.